601 research outputs found
Ineffective corporate governance: Busyness of internal board monitoring committees
We examine whether the voluntary formation of a Risk Committee (RC) compromises the effectiveness of other monitoring duties carried out by the board members. We argue that adding more monitoring committees increases the board’s internal busyness, which reduces the effectiveness of monitoring by the Audit Committee (AC). Using a sample of financial firms over the period 2007 to 2011 from the Gulf Cooperation Countries (GCC), we find that voluntarily adopting a risk committee impairs the effectiveness of the audit committee, which in turn reduces financial reporting quality. Our findings suggest that multiple layers of monitoring capacity viz-a-viz the existence of both an audit and risk committee may weaken the quality of monitoring provided by the audit committee
Underdetermined convolutive source separation using two dimensional non-negative factorization techniques
PhD ThesisIn this thesis the underdetermined audio source separation has been considered, that is, estimating the original audio sources from the observed mixture when the number of audio sources is greater than the number of channels. The separation has been carried out using two approaches; the blind audio source separation and the informed audio source separation. The blind audio source separation approach depends on the mixture signal only and it assumes that the separation has been accomplished without any prior information (or as little as possible) about the sources. The informed audio source separation uses the exemplar in addition to the mixture signal to emulate the targeted speech signal to be separated. Both approaches are based on the two dimensional factorization techniques that decompose the signal into two tensors that are convolved in both the temporal and spectral directions. Both approaches are applied on the convolutive mixture and the high-reverberant convolutive mixture which are more realistic than the instantaneous mixture.
In this work a novel algorithm based on the nonnegative matrix factor two dimensional deconvolution (NMF2D) with adaptive sparsity has been proposed to separate the audio sources that have been mixed in an underdetermined convolutive mixture. Additionally, a novel Gamma Exponential Process has been proposed for estimating the convolutive parameters and number of components of the NMF2D/ NTF2D, and to initialize the NMF2D parameters. In addition, the effects of different window length have been investigated to determine the best fit model that suit the characteristics of the audio signal. Furthermore, a novel algorithm, namely the fusion K models of full-rank weighted nonnegative tensor factor two dimensional deconvolution (K-wNTF2D) has been proposed. The K-wNTF2D is developed for its ability in modelling both the spectral and temporal changes, and the spatial covariance matrix that addresses the high reverberation problem. Variable sparsity that derived from the Gibbs distribution is optimized under the Itakura-Saito divergence and adapted into the K-wNTF2D model. The tensors of this algorithm have been initialized by a novel initialization method, namely the SVD two-dimensional deconvolution (SVD2D). Finally, two novel informed source separation algorithms, namely, the semi-exemplar based algorithm and the exemplar-based algorithm, have been proposed. These algorithms based on the NMF2D model and the proposed two dimensional nonnegative matrix partial co-factorization (2DNMPCF) model. The idea of incorporating the exemplar is to inform the proposed separation algorithms about the targeted signal to be separated by initializing its parameters and guide the proposed separation algorithms. The adaptive sparsity is derived for both
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of the proposed algorithms. Also, a multistage of the proposed exemplar based algorithm has been proposed in order to further enhance the separation performance.
Results have shown that the proposed separation algorithms are very promising, more flexible, and offer an alternative model to the conventional methods
Three essays on market risk disclosures: corporate governance, investment efficiency and implied cost of equity capital: evidence from gulf cooperation council countries (GCC).
This thesis examines the association between market risk disclosures and corporate governance, investment efficiency and implied cost of capital. The results show firms that have adopted risk management committee increase the market risk disclosures (both quality and extent). In addition, firms that disclose more market risk disclosures (both quality and extent) improve investment efficiency by reducing (both over-under investment). Market risk disclosures also reduce the firm’s implied cost of equity capital
An Overview of Grammar Translation Method’s Effect on EFL Teaching And Learning
In language teaching and learning, several methods are used for the effectiveness of teaching and learning activity. The researcher implemented the methods to assist the teacher in teaching the language, time after time. The methods have undergone many changes and development based on the attitude and school of thought for teaching and learning a language, so each method has a different character, technique, and implementation. This reflection will expand on the grammatical translation method (GTM) used in the nineteenth century to teach English as a foreign language. This method is based on the goal of grammatical competence. To achieve the goal, this method has several characteristic and technique which will be used in its implementation. The writer attempts to do a review by investigating 5 published articles gathered from internet websites to show the use of the grammar-translation method, its effectiveness, and why it is criticized for teaching and learning English as a foreign language. The writer’s reflection is included too
Physiological Studies on Growth and Reproduction of Sclerotinia sclerotiorum Causing White Rot on Eggplants under Laboratories Conditions
هدف البحث دراسة أهمية بعض الظروف الفسيولوجية على نمو الفطر Sclerotinia sclerotiorum (مسبب العفن الأبيض على نبات الباذنجان) وأنتاجهُ للتراكيب التكاثرية (الأجسام الحجرية). إذ نفذت سلسلة من التجارب المختبرية حول الخصائص الفسيولوجية لهذا الفطر يإستعمال أنواع مختلفة من الأوساط الغذائية ودرجات الحرارة والحموضة والتراكيز الملحية.
اظهرت النتائج أن لنوع الوسط الغذائي تاثيراً معنوياً ( (0.05على معدلات نمو الفطر S. sclerotiorum وعلى قدرتهُ في تكوين الأجسام الحجرية، إذ أزداد نمو الفطر الممرض معنوياً في وسط أوراق المورنكا Moringa oleifera (Mo) لكنه انخفض معنويا في وسط المعدنوس Petroselinum crispum (Pc) بالمقارنة مع الوسط PDA. وفي المقابل فان تكوين الأجسام الحجرية تضاءلت معنويا في وسط Pc لتصل الى 4 جسم حجري/ طبق تلاه الوسط Mo (7 جسم حجري/ طبق) بالمقارنة مع الوسط PDA (25 جسم حجري/طبق). وبلغ اعلى معدل لنمو الممرض على وسط PDA في اليوم السابع على درجة حرارة 20 مْ ، تلاها النمو على درجة حرارة 25 مْ ثم 15 مْ وياتي بعدها 30 مْ واقلها نموا على درجة حرارة 35 مْ . كما ان مستوى الحموضة المثالي لنمو هذا الفطر هو 5.5، في حين انخفض تكوين الأجسام الحجرية بنسبة 44% عند مستوى الحموضة 4.5 ومع أرتفاع قاعدية الوسط الى 8 أنخفض أعداد الأجسام الحجرية المنتجة بنسبة 84% بالمقارنة مع النمو على pH = 5.5.
ان التراكيز الملحية (NaCl) 4% و6% و8% كانت مثبطة لانتاج الأجسام الحجرية وتناقصت إعدادها وتشوهت اشكالها عند التركيز 4% وبعد هذا التركيز فشل الفطر الممرض في انتاج الأجسام الحجرية. نستنتج ان هذه الدراسة قد سلطت الضوء على عناصر الوبائية لهذا المرض والتي تكمن اساسا في تطبيق استراتيجية ادارة المرض.This study was aimed A series of laboratory experiments were carried out, including the study of the physiological characteristics of the Sclerotinia sclerotiorum, especially the effect of type of medium, temperature, acidity and saline concentrations on the growth of the pathogen and on its production capability on reproductive structures (sclerotia).
Results showed that the type of media had a significant effect (0.05) on growth average of S. sclerotiorum and on its ability to produce sclerotia. The growth of the fungus was significantly higher in Moringa oleifera leaves medium (Mo), but substantially decreased in Petroselinum crispum (Pc) compared to that in PDA. In contrast, the formation of sclerotia substantially decreased in Pc medium (4 sclerotia/ plate) followed by Mo (7 sclerotia/ plate) compared with PDA (25 plate / plate). The highest rate of growth of S. sclerotoirum was at 20 oC on the seventh day after inoculation, followed by growth at 25 oC and at 15 oC followed by 30 oC and the lowest growth was at 35 oC. It was found that the optimum pH for growth of S. sclerotiorum was at 5.5, but when pH increased to 4.5 the production of sclerotia was minimized to 44%. Also, the increasing of alkalinity to 8% resulted in a decrease of fungal growth to about 84% compared to the growth at pH = 5.5.
Salt concentrations (4%, 6%, and 8%) were revealed inhibitory effect on sclerotia production by S. sclerotiorum, but this effect negatively correlated with increasing concentration of NaCl. The results also showed a reduction in their production and deformity in their shaps at 4% concentration. After this concentration, fungus failed to produce the sclerotia. It can be concluded that this study highlighted the epidemiological components of the disease, which lie mainly in the application of the disease management strategy.
 
COVID 19,Risk of Infection and Biosafety Protocols in Diagnostic Laboratories
على مدى العقود القليلة استطاعت التقارير المختبرية توثيق العديد من حالات الإصابات بالأمراض المعدية ضمن العاملين في هذه المختبرات. حوالي 80% من هذه الحالات يعتقد بكونها مرتبطة ارتباطا مباشرا بالرذاذ الجوي داخل المختبر نتيجة العمل مع عينات من المحتمل ان تكون معدية. الجزيئات الصغيرة السائلة او الصلبة لهذا الرذاذ قد تبقى لفترة طويلة داخل جو المختبر أو قد تنتشر لمسافات بعيدة حيث يتم استنشاقها بسهولة. يمكن لهذه الجزيئات أن تترسب بسهولة على الاسطح المختلفة مثل الجلد او انظمة التهوية خصوصا اذا كانت اقطارها اكثر من 5 مايكرون. نتيجة لما سبق أصبح من الواجب اتباع خطوات أو إجراءات فعالة ومنتظمة لحماية العاملين في المختبرات بالإضافة الى حماية البيئة أو تقليل انتاج مثل هذا الرذاذ الجوي. بعض الإجراءات تتضمن قياس مدى خطورة الرذاذ الجوي عندما تكون إجراءات السلامة البايولوجية عند مستوى P2 او المستويات الاعلى من ذلك ضرورية للقيام بالتجارب المختبرية. في معظم الحالات, يجب ان تكون معدات السلامة و كافة الاجراءات الوقائية متوفرة داخل المختبر وفي جميع الاوقات وأن تكون ملائمة للمستوى المطلوب من السلامة البيولوجية لاي عمل مختبري (بما في ذلك العوامل البيولوجية, فايروس كوفيد 19). من الواجب حماية العاملين في المختبرات الذين يتعاملون من عينات مشتبه بها او مؤكدة الاصابة بفايروس كوفيد 19 . إجراءات السلامة الجيدة أصبحت مشخصة لتفادي ضرر إنتشار العدوى بفيروس سارس كوفيد 19. من المتوقع إن جميع الاجراءات الوقائية القياسية تكون متبعة من قبل العاملين في المختبرات والمذكورة في الارشادات العامة للمختبرات والتي تتماشى مع الاجراءات القياسية. هذه الإجراآت القياسية المتعلقة بمتطلبات السلامة البايولوجية يجب أن تطبق عند التعامل مع عينات افيروس سارس كوفيد 19. تشمل هذه الإجراىت القياسية المختبرات الميكروبيولوجية والسرسرية التي تتعامل مع عينات الدم ، المصل ، البلغم او غيرها من العينات المتعلقة بالبحوث.Over several decades, plenty of records of lab. workers contracting disease due to the infectious materials have been documented. About 80 percent of these cases are thought to be directly associated with the formation of aerosols during the lab. works with potentially infectious samples. Small liquid or solid particles of aerosols suspended in the air for a while or spread over a wide range of distances and then inhaled easily. However, they can be settled rapidly on surfaces such as skin and ventilation systems if the diameters of particles are higher than 5 microns. Effective steps should regularly be used to protect staff and the environment, or to reduce the extent of the aerosols production. Measures containing the aerosol are to be applied where physical containment at practice 2(P2) and above levels is needed for the research operation.
In most cases the safely equipment’s and precautions must be available in all time in the lab. and comply with the required level of Biosafety for any type of the laboratory work (including the relevant biological agents, SARS-CoV-2 in this case). Staff who working with suspected or confirmed specimens of COVID-19 or of SARS-CoV-2 should be completely protected from such infectious materials. Good biosafety practices have been recognized to avoid or mitigate the spread of infection (i.e., SARS-CoV-2). Standard precautions expected to be already used by laboratories as stated in the general guidelines and they should follow standard laboratory practices. Practices related with these biosafety requirements must be proceed when dealing with samples/specimens from SARS-CoV-2. This involves microbiological as well as clinical laboratories conducting routine serum, blood, sputum (respiratory) and other sample diagnostic, analytical, or other research-related studies
The Issues in Which Sibawayh Made a Mistake in the Book ``Ea'arab of the Qur'an'' for An-Nahas/A Grammar Study
This study sheds light on the issues in which Sibawayh made a mistake in the book ``Ea'arab of the Qur'an'' for An-Nahas, a grammatical study, where I enumerated these issues and edited them by presenting and discussing the evidence and then concluded them with the opinion of the researchers, with a clear statement of misleading. All this stems from justice and truth, far from fanaticism or inclination toward one scholar without another. The research was divided into an introduction and a preface that included a brief translation of Mark Al-Nahas and a definition of confusion both linguistically and idiomatically, then the issues that Al-Nahas made mistakes in Sibawayh and the issues in which other scholars were mistakenly transferred to Sibawayh. Finally, a conclusion that included the most important results extracted from the research and a list of the most essential approved sources.
Keywords: Al-Nahas, Sibawayh, mistake, mubrad, Basroun, Kufi
Consequences of local social norms: A review of the literature in accounting, finance, and corporate governance
We synthesise the empirical archival research on the consequences of local social norms on accounting, finance, and corporate governance outcomes in an international setting. The literature reviewed is premised on the theory that corporations do not make decisions, but managers do, and managers are likely to be influenced by the socioeconomic environment of the region in which they operate and/or by the people with whom they interact. To provide a structure to our review, we identify social capital, religiosity, gambling norms, and corruption culture, as four constructs of local social norms and link these with financial reporting and external auditing, financial, investment, and dividend decisions, capital market consequences and finally, corporate governance and corporate social responsibility behaviour of firms. We highlight some limitations of the existing research and offer some suggestions for future research
The Effect of Adding Graphite on the Structural and Mechanical Properties of Titanium Carbide
السيراميك المتقدم يمتلك تطبيقات عديدة مثل الفضاء، الحراريات ، الطبية ، الالكترونية .......الخ. في العمل الحالي تحضير كاربيد التيتانيوم باستعمال ميتالورجيا المساحيق من التيتانيوم و الكرافيت عند درجة حرارة (1200 م°) و فترة مكوث (8) ساعة حيث تم تحضير كاربيد التيتانيوم باستعمال نسب وزنية مختلفة وهي ((14:86) ، (17:83) ، (20:80) و (23:77)) للتيتانيوم والكرافيت على التوالي.
دُرست الخواص الميكانيكية (الصلادة المايكروية ،مقاومة الانضغاط و مقاومة البلى) و الخواص التركيبية (المجهر الالكتروني الماسح و حيود الاشعة السينية) لعينات كاربيد التيتانيوم . اوضحت النتائج ان افضل خواص الميكانيكية لعينات كاربيد التيتانيوم عند النسبة الوزنية (20:80) للتيتانيوم والكرافيت على التوالي.The advances ceramics have many applications such as aerospace, refectory, medical, electronic,…etc. In this work, the preparation of titanium carbide by using powder metallurgy technique from titanium and graphite has been investigated with different weight percentages are ((86:14),(83:17),(80:20) and (77:23)) wt.% titanium and graphite respectively. Titanium carbide was formed at (1200°C) for (8hr). The mechanical properties (microhardness, compression strength and wear rate) and characterization (SEM and XRD) of titanium carbide samples were studied. The results found that the best mechanical properties for titanium carbide samples prepared at (80:20) wt.% titanium and graphite respectively
Diagnostic study on Herpes simplex-1
The study was planned to evaluate the prevalence of HSV-1 infection, and the use of rhabdomyosarcoma and L20B as cell lines for the primary propagation of human herpes simplex1, by using modern diagnostic techniques. The study was involved in a collection of 60 samples from dermal lesions, randomly selected from a population of ages ranges from 15 to 45 years. These samples were collected during a period extended from February to September 2013. Primarily, these samples were investigated by RT-PCR technique directed to certify human herpes simplex-1 infections. Bosphore® HSV-1&2 Genotyping Kit v1(Anatolia gene works, Turkey) was used for the detection protocol. From a total of 47 HSV-1 positive samples in PCR step, 20 samples were cultured using two cell lines (Rhabdomyosarcoma (RD) and L20B cell lines) in an attempt for virus isolation and evaluation capability of these cells for HSV-1 propagation. Results of applied PCR revealed that HSV-1 DNA was correlated with 47(78.3%) positive of the total cases investigated. In the attempt to HSV-1 isolation, both RD and L20B cell lines demonstrated a specific HSV-1 cytopathic effect. Herpes simplex virus type 1 had been propagated in 19 (95%) of the 20 PCR positive isolates by RD cell line, while 17:20 (85%) HSV-1 isolates were positive on L20B cells. In conclusions: The thermal protocol for Bosphore® HSV-1 Genotyping Kit v1allows very rapid detection of HSV-1 DNA in dermal lesions. It is finding to be laborsaving and shows sufficient sensitivity. The RD and L20B cell lines are efficient as cell lines for the propagation of HSV-1, for that It is well recommended to achieve future therapeutic studies on HSV-1
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